Convert VOXEL model to soft Mesh
I can't tell you how to import voxel data into Blender, but if there's no dedicated importer, you can try MeshLab to convert to a supported format. For example, PLY or STL to import as vertices. If there's no real surface yet, you may use MeshLab's pointcloud triangulation capabilities and export as .OBJ.

Once you have a mesh object in Blender with a surface, try the Laplacian Smooth Modifier, which lets you smooth mesh surfaces while retaining a lot of detail.  Go to Properties Editor > Modifiers and add it to your object.

More information: official documentation